In contrast, Merck & Co. Inc.’s sales for the first quarter of 2009 fell a mere 8% from the year-ago period. However, foreign exchange rates negatively affected its global sales performance by 3%. Schering-Plough Corp.’s sales fell 6%, reflecting 4% operational growth and a negative impact from foreign exchange of 10%.

And Johnson & Johnson’s first-quarter 2009 worldwide sales of pharmaceuticals slid 10.1% from the year-ago period, with an operational decline of 5.1% and a negative impact from currency of 5.0%. Since operational growth excludes the effect of currency, this means that about half the losses are due to lower sales volumes of the drugs per se.

Digging deeper, we find that five of J&J’s top drugs suffered lower sales due to operational losses: Levaquin, Procrit (due to a decline in the market), Razadyne, Risperdal (due to generic competition), and Topamax. But six others recorded higher (operational) sales: Aciphex, Concerta, Duragesic, Remicade, Risperdal Consta, and Velcade.

Indeed, J&J’s sales of Remicade (an anti-TNF antibody-based therapy for rheumatoid arthritis and other inflammatory disorders of the immune system) in the U.S. increased 3% to slightly more than $1 billion in the first quarter 2009 from the year-ago period (on both an “as reported” basis and an operational basis). Schering-Plough (SGP) sells the blockbuster in countries outside the U.S. (except in Japan and certain other markets) – and even through Remicade is continuing to gain market share in these countries, its sales took a significant hit, dollar-wise, due to the strong dollar. In the first quarter of 2009, SGP said, sales of Remicade increased 2% (22% operational growth offset by 20% unfavorable foreign exchange impact) due to continued market growth and expanded penetration in certain indications.

One of Remicade’s top competitors is Humira, another anti-TNF antibody marketed by Abbott Laboratories. First-quarter 2009 worldwide sales of Humira cleared the $1 billion mark: Operational sales increased nearly 28% compared to the year-ago period, but unfavorable exchange rates pared that gain to about 17%.

Big pharma Wyeth was also affected by the recession: The company’s worldwide net revenues for the first quarter of 2009 dipped 6% from the year-ago period. However, here again foreign exchange rates were largely to blame for the decline. Excluding the unfavorable impact of foreign exchange, Wyeth said, worldwide net revenue increased 2% for the first quarter of 2009. Higher sales of Wyeth’s key drugs Prevnar (a pneumococcal vaccine for infants and toddlers) and Enbrel (ex-U.S. and Canada) helped power the gain of 2% overall. On an as-reported basis (which includes the effect of foreign exchange), sales of Prevnar rose by 7% and sales of Enbrel rose by 3%. But excluding the effect of foreign exchange, Prevnar sales rose by 19% and Enbrel sales soared 23%.

Because a strong dollar lessens the value of overseas sales, it’s to be expected that Wyeth’s sales of Enbrel suffered. But how did Amgen Inc. do in its territories (U.S. and Canada) during the first quarter of 2009? Well, sales of Enbrel took a big hit, down 20% from the year-ago period. According to Amgen, this decline was driven primarily by unfavorable changes in wholesaler inventory and to a lesser extent a decline in demand, which the company said was principally due to a decrease in the units sold partially offset by an increase in price. The decrease in units, it explained, was due not only to sales of competitive products but also to a slowdown in the growth of the entire market for TNF-blockers.

Sales of Amgen’s other key products were affected by the economic downturn, as well – especially those that it markets on a worldwide basis. For instance, in the first quarter of 2009, global sales of Aranesp decreased 18% compared to the first quarter of 2008. U.S. sales of Aranesp decreased 21% (excluding the impact of accounting estimates), principally driven by a decline in demand. Amgen attributed this decline to two factors: product label changes which restrict the product’s use, especially in cancer, and loss of market share. International sales of Aranesp decreased 6%, primarily due to the negative impact of foreign exchange rates.

Combined worldwide sales of Amgen’s white blood cell boosters Neulasta and Neupogen decreased 1% in the first quarter of 2009. In the U.S., combined sales of these products increased 1%, largely due to an increase in the sales price, partially offset by a decrease in the number of units sold. International sales, not surprisingly, dipped 6%, due to unfavorable foreign exchange rates. Excluding that factor, combined worldwide sales increased 1% and international sales increased 4%.

On the other hand, sales of Epogen, Amgen’s first-generation EPO which it markets in the U.S., increased 2% in the first quarter of 2009 due to patient population growth and an increase in price. And worldwide sales of Sensipar, which is used to treat secondary hyperparathyroidism in patients with chronic kidney disease and to treat elevated levels of calcium in patients with parathyroid carcinoma, increased 11% in the first quarter of 2009, due to increased demand.

According to prepared remarks by Kevin Sharer, Amgen’s chairman and CEO, “Our first quarter sales were affected by the continued deterioration of the global economy which has led to changes in patient and physician behavior.” In a conference call, he added that patients are putting off visits to their doctors and cutting back on – or even stopping – their medications.

Indeed, this is exactly what we’d like to know. While lowered sales due to unfavorable changes in currency exchange rates (or even wholesaler inventories and the like) are real enough, they don’t reflect a bona fide decrease in demand. Factors that do play a role, as we’ve already noted, include label changes for a particular drug (which restrict the conditions under which it can be used); competition for market share from a newer, better version of a prescribed drug or a generic equivalent; and a tight economy, in which consumers find themselves either unwilling or unable to pay for their medicines, especially expensive biological therapies.

To this end, we’ve analyzed first quarter 2009 sales of 35 biotech-derived blockbusters. In the tables that follow, we’ve sorted the products based on their 2008 annual sales, from top-dog Enbrel (which reaped nearly $6.2 billion in sales last year) to recombinant DNA pioneer Humulin (which cleared slightly more than $1 billion in 2008, its 26^th year on the market).

We’ve recorded the percent change in sales for the first quarter of 2009 with those from the year-ago period for these products. These are sales on an “as reported” basis, which take into account the changes in foreign exchange rates for the first quarter of 2009.

Where possible, we’ve teased out the “real” or actual sales figures, although they also come with many caveats (see Amgen’s explanation of its combined sales of Neulasta and Neupogen, as described above).

Surprisingly, perhaps, most biotech companies reported increased sales of their lead drugs in the first quarter of 2009, although in many cases negative currency exchange rates took their toll.

Genzyme Corp.’s total revenue, for instance, rose 4% from the year-ago period -- although without the impact of exchange rates revenues would have grown 10%. Sales of Myozyme, an enzyme replacement therapy for Pompe disease, were essentially flat due to supply constraints. Sales of Cerezyme, the firm’s blockbuster therapy for Gaucher disease, fell 3% due to negative exchange rates. Without that influence, Cerezyme’s sales grew 5% in the first quarter of 2009, in line with Genzyme’s statement that it continues to see growth in the number of patients starting therapy, especially in international markets.

Gilead Sciences Inc.’s HIV drugs Truvada and Atripla have also reached blockbuster status. Worldwide sales of Truvada increased 23% to $590 million in the first quarter of 2009, while Atripla’s sales jumped 57% to $510 million in the first quarter. According to Gilead, both increases were driven primarily by sales volume growth in the U.S. and Europe. Even so, negative currency exchange rates had a significant and unfavorable impact on Gilead’s first quarter revenues and pre-tax earnings (to the tune of $22.3 million and $11.7 million, respectively).

Net sales of Celgene Corp.’s lead drug Revlimid, approved for treating multiple myeloma and myelodysplastic syndromes, increased 26% over the year-ago period. This increase represents gains in global market share and increased numbers of patients, prescriptions and duration of therapy, the company said. Still, analysts had expected more from Revlimid: It might not be apparent at first glance, but the global recession has affected sales of this drug, too.

Biogen Idec Inc.’s first quarter 2009 revenues were slightly greater than $1 billion, an increase of 10% as compared to the first quarter of 2008. Revenues grew for all three of the company’s products: Tysabri’s revenues grew 44%, Avonex’ revenues grew 4%, and Biogen Idec’s share of Rituxan’s revenues (as recorded by its partner Genentech) grew 13%.

Biogen Idec attributed Tysabri’s growth to an increase in the number of patients using the drug, both in the U.S. and internationally. It also said that U.S. sales of Avonex increased 10.2% from the year-ago period, primarily due to a price increase, but partially offset by a decrease in demand. International sales of Avonex, on the other hand, decreased 5.4% due to the negative impact of exchange rates, partially offset by price increases.

While Biogen Idec’s share of Rituxan’s sales increased 13% in the first quarter of 2009, we really need to look at the Roche/Genentech data to get the full picture. According to Biogen Idec, Genentech said that U.S. sales of Rituxan for the first three months of 2009 were $642 million, a 6% increase from the year-ago period. According to Roche (which completed its acquisition of Genentech on March 26, 2009 and thus reported combined worldwide sales for all therapies), first quarter 2009 sales of Rituxan/MabThera were 1.48 billion Swiss francs (about $1.3 billion), a 5% jump from the first quarter of 2008 on higher sales.

In fact, most of Roche’s biological therapies recorded higher sales in the first quarter of 2009 than they had in the year-ago period. Importantly, the increases reflect sales of more units rather than price hikes. (See the accompanying tables for details.) However, combined sales of the recombinant red blood cell boosters NeoRecormon (a Roche product) and Epogin (a Chugai product) declined 14% to 378 million Swiss francs, largely due to continued price pressure in a highly competitive market.

Roche also records its portion of sales of a handful of biotech-derived therapies that are partnered with other firms. For example, Roche holds the U.S. rights to Lucentis, a fairly new therapy for treating wet age-related macular degeneration, while Novartis markets it elsewhere. Roche reported a 30% increase in Lucentis sales in the first quarter of 2009, while Novartis reported a 43% increase in sales (in local currencies), which translates to a 17% increase in U.S. dollars. Here again, the negative impact of exchange rates is obvious. (In fact, the negative currency impact significantly affected Novartis’ first quarter 2009 results; net sales overall were down 2% in U.S. dollars but up 8% in local currencies.)

Roche and Novartis have also teamed up on Xolair, a monoclonal antibody-based therapy for allergic asthma. Roche reported Xolair sales of 152 million Swiss francs (about $133 million), up about 22% from the year-ago period. For its part, Novartis reported sales of $61 million for the first quarter of 2009, a 77% jump (in local currencies) from the year-ago period.

Tarceva, a small molecule cancer drug, is co-promoted by OSI Pharmaceuticals Inc. and Roche. U.S. sales of Tarceva for the first quarter of 2009 amounted to $111 million, unchanged from the year-ago period. But overseas sales increased 12% during the same time frame.

Roche was also paired with German pharma Merck KGaA to sell the psoriasis therapy Raptiva, but the partners withdrew the product from all markets in April 2009 after three patients came down with progressive multifocal leukoencephalopathy (PML), an oft-deadly viral infection that first popped up in patients taking Tysabri for multiple sclerosis in early 2005.

As with most biotech blockbusters, ImClone Systems Inc.’s anti-EGFR cancer therapy Erbitux is marketed through a number of different partners. ImClone’s partner Bristol-Myers Squibb Co. (BMS) holds the marketing rights in the U.S., Canada and Japan; Merck KGaA holds the rights worldwide except the U.S. and Canada. Eli Lilly & Co., which acquired ImClone in November 2008, expects to gain the U.S. and Canadian rights in 2018 when the BMS agreement expires.

In the first quarter of 2009, BMS reported that Erbitux sales in the U.S. were down 12% from the year-ago period. The company explained that the decrease was “primarily due to study results released in 2008 regarding the impact of the K-ras gene expression on the effectiveness on patients with colorectal cancer.” Those studies demonstrated that metastatic colorectal cancer patients with tumors carrying a normal (wild type) KRAS gene (about 65% of the population) are the most likely to benefit from treatment with Erbitux.

Curiously, Merck KGaA said that first-quarter 2009 Erbitux sales increased by about the same amount, which some analysts attributed to the availability of this genetic test.

We’ve detailed the sales figures and negative effects of foreign currency exchange rates for about half of the blockbuster drugs included in the tables, but if you scan the others you’ll find similar stories throughout.

All told, then, the worldwide economic crisis has taken a bite out of drug sales by big pharma conglomerates and biotech companies alike. But most of the damage has been caused by unfavorable currency exchange rates, rather than reduced sales of the drugs per se. Were that to occur in this inhospitable economic environment, it would probably mean that consumers are cutting back on purchases of pricey medications. Since virtually every biological therapy is expensive, this scenario is particularly disturbing to the companies that develop and market these medicines.

Gloomy projections by IMS Health Inc., which tracks prescription drug data, only increase the level of concern. Weeks after the close of the first quarter this year, IMS lowered its 2009 global pharmaceutical market forecast to 2.5% - 3.5% growth on a constant dollar basis –- 2% lower than it had predicted in October 2008, “as deterioration in the global economic environment continues to affect market demand.” IMS also said that the pharmaceutical sector will “feel the impact of the economic climate through 2010, when a rebound is expected.”

In prepared remarks, Murray Aitken, SVP, Healthcare Insight, IMS, said “There is a clear correlation between demand for medicines and key macroeconomic variables such as GDP, consumer spending and government expenditures. We see the worldwide financial crisis contributing to record-low sales growth this year.”

So keep these factors in mind when the six-month earnings reports start coming out in July. And don’t be discouraged by lower sales figures for the biotech blockbusters unless they actually reflect lower demand by cost-wary consumers.